Device and method for placing a roll against/removing it from a printing press

ABSTRACT

A device is provided for engaging and/or disengaging a roller with or from a first mating roller. The device includes a second mating roller, with which the roller is engaged, and with a basic unit, with which the roller can be moved to or away from the first mating roller in the circumferential direction of the second mating roller. A process for engaging and/or disengaging a roller of a printing press with or from a first mating roller is provided wherein the roller is engaged with a second mating roller and the roller is guided in the circumferential direction of the second mating roller in the state in which it is engaged with the second mating roller.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a United States National Phase application ofInternational Application PCT/CH2004/000540 and claims the benefit ofpriority under 35 U.S.C. § 119 of German Application DE 103 40 183.0filed Sep. 1, 2003, the entire contents of which are incorporated hereinby reference.

FIELD OF THE INVENTION

The present invention pertains to a device and a process for engagingand disengaging a roller of a printing press with and from a matingroller.

BACKGROUND OF THE INVENTION

It is frequently necessary during the printing operation to engage anddisengage individual rollers with and from other rollers. Individualrollers, e.g., an applicator roller, are engaged in such casessimultaneously with both a plate cylinder and a distributor roller, anda so-called “nip,” i.e., a contact surface, at which the surfaces of therollers that are in contact with one another touch each other, is formedin the area of the contact between two rollers that are in contact withone another. It is generally preferred that a roller be in contact witha mating roller with the most constant pressure possible.

A device for mounting and positioning a roller of a printing press, inwhich the roller is engaged with at least one mating roller and ismounted on both sides in a bearing shell, is known from the Applicant'sDE 198 11 053 A1, whose teaching concerning the mounting and positioningof a roller is included in this application. These bearing shells areconnected with a press frame by means of at least one spring element.

FIG. 3 shows a so-called intermediate roller 1, which is engaged withtwo stationary mating cylinders 3 and 4. The intermediate roller 1 isengaged with the mating rollers 3 and 4 usually along the bisecting lineof the angle of the triangle formed by the axes of rotation of therollers 1, 3 and 4, starting from the axis of rotation of roller 1,between the two axes of rotation of the rollers 3 and 4 and it comessimultaneously in contact with the mating rollers 3 and 4.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a device and a processfor engaging and/or disengaging a roller of a printing press with/from amating roller, which make possible rapid engagement and disengagementoperations.

According to the invention, a device is provided for engaging and/ordisengaging a roller with or from a first mating roller. The deviceincludes a second mating roller, with which the roller is engaged, and abasic unit, with which the roller can be moved to or away from the firstmating roller in the circumferential direction of the second matingroller.

According to a further aspect of he invention, a process for engagingand/or disengaging a roller of a printing press with or from a firstmating roller is provided wherein the roller is engaged with a secondmating roller and the roller is guided in the circumferential directionof the second mating roller in the state in which it is engaged with thesecond mating roller.

A roller shall be engaged according to the present invention such thatit is in contact with at least two rollers in the engaged state. Thishappens, e.g., in the case of an applicator roller that shall be incontact with a distributor roller and a plate cylinder.

The device according to the present invention for engaging and/ordisengaging a roller of a printing press with or from a first matingroller, so that the roller is in contact with the first mating rollerand with a second mating roller in the engaged state, has a basic unit,with which the roller can be guided or moved in the circumferentialdirection or in the tangential direction of the second mating rollersuch that the roller is preferably continuously in contact with thesecond mating roller and can thus be moved, e.g., along a circular pathin the direction of the first mating roller until the roller comes intocontact with the first mating roller. Likewise, the roller can also bemoved away from the first mating roller with the basic unit. The basicunit provided according to the present invention is consequentlydesigned such that the roller can be mounted or guided along the secondmating roller such that at least one partial area of the surface of theroller and of the second mating roller preferably touch each otherwithout interruption, i.e., that the roller is preferably engagedcontinuously with the second mating roller. As a result, the roller canalready rotate together with the second mating roller in contact with itand if, e.g., an applicator roller is in contact with a distributorroller and is guided along the surface of the distributor roller forengaging with a plate cylinder, the applicator roller can be preventedfrom running dry. Thus, the roller needs to be engaged according to thepresent invention with a single mating roller only, because it ispreferably already in continuous contact with the second mating roller.

Thus, it is possible according to the present invention to set thecontact between the roller and the mating roller that is in contacttherewith already before the roller is engaged with the additionalmating roller. For example, the nip can already be set and only a singleengaging operation with an additional mating roller is necessary tobring the roller into contact with two mating rollers.

Thus, control units for positioning the roller to be engaged can besimplified with the device according to the present invention and, e.g.,electric motors and potentiometers for the simultaneous engagement ofthe roller with two mating rollers in the correct position withcorrespondingly complicated actuating mechanisms can be eliminated.

The device according to the present invention for engaging and/ordisengaging a roller with or from a mating roller may be provided, inprinciple, for every individual roller of a printing press. The presentinvention is preferably used for at least one, several or each rubbercylinder, for example, in the inking system and/or in the dampeningsystem. For example, rider rollers, distributor rollers, ink applicatorrollers and/or other rollers that are directly or indirectly adjacent tothe rollers can be engaged or disengaged with the device according tothe present invention or with the process according to the presentinvention. It is possible, in principle, with the device according tothe present invention or with the process according to the presentinvention to engage or disengage one, two or even more rollers in aprinting press or in a printing couple with or from one, two or morethan two mating rollers together or independently from one another.

The basic unit advantageously has a pneumatic element for adjusting thebasic unit, as a result of which very fast engaging and/or disengagingmovements can be carried out and it is thus possible, e.g., to embodysteep run-up sequences with a minimum amount of spoilage or fastdisengagement operations, e.g., in case of an emergency stop, whilecurling in inking systems is avoided at the same time.

To move the roller in the circumferential direction of the second matingroller, the basic unit can be preferably adjusted transversely, i.e., atright angles to a radial direction or in parallel to a tangentialdirection of the second mating roller. As a result, it becomes possibleto set any desired nip ratio between the roller and the first and secondmating cylinders. If the basic unit is moved, for example, to a matingroller in a straight-line continuation of a tangential direction, thepressure distribution on the contact surfaces of the roller on the firstand second mating cylinders can be set and it can thus be ensured, forexample, that the same nip is always present at the contact points onthe first and second mating rollers. For example, the nip ratio betweenan applicator roller and a plate cylinder or the distributor roller canbe set or adjusted in one embodiment by a corresponding transverseadjustment of the basic unit in relation to the distributor rollerand/or to the plate cylinder.

A feed unit is advantageously provided, which is in connection with theroller or in which the roller is mounted and with which, e.g., anengaging pressure of the roller on one or two mating rollers can be setor generated. The feed unit may be connected, e.g., rotatably or rigidlyto the basic unit.

The feed unit preferably has a carriage for this purpose, on whichpressure is applied, e.g., by a spring or another suitable element andcan mount the roller, e.g., an applicator roller, in the known manner intwo half shells.

A setting element, e.g., an adjusting spindle, is advantageouslyprovided, with which a pressure, e.g., the spring pressure on thecarriage, can be changed in order to set the engaging pressure of theroller mounted in the carriage on the mating cylinder or matingcylinders can be set and, for example, desired nip widths can beachieved at the mating cylinders, i.e., for example, at the platecylinder and at the distributor roller,

The feed unit is preferably located in the axis of the bisecting line ofthe angle between the first and second mating cylinders, i.e., forexample, between the plate cylinder and the distributor roller, e.g., inthe engaged state, as a result of which the engaging pressure generatedby the feed unit and acting on the roller acts approximately uniformlyon the two mating cylinders, so that the nip ratio between the matingcylinders is approximately equal. However, the nip ratio can be changedby deflecting the feed unit or the element provided for generating theengaging pressure, for example, a spring, from the mentioned bisectingline of the angle in order to generate, for example, a greater nip widthin one mating cylinder than in another mating cylinder.

The basic unit and the feed unit are preferably coupled with one anotherand are advantageously mounted such that they are rotatable in relationto one another, so that, for example, the roller is connected to thebasic unit via the feed unit and the basic unit can guide the rollertogether with the feed unit in the circumferential direction of thesecond mating roller such that the roller is engaged with or disengagedfrom the first mating roller. The feed unit can now be rotated into sucha position that a spring element present in the feed unit presses acarriage carrying the roller such that a desired nip ratio can beachieved.

Thus, rollers can be engaged and disengaged very rapidly by means of thedevice according to the present invention, and it is possible to set anip or even a nip ratio that is preserved regardless of the velocity,heating of the rollers or in case of a possible swelling or shrinkage orcan also be regulated automatically. It is thus possible to embody anapplicator roller bearing that automatically compensates the nip, andthe nips can also be adapted to changes within certain limits.

Printing units with plate cylinders with very small channel widths,e.g., with a minigap slot splitting, or channelless plate cylinders,e.g., of the sleeve design, are advantageously used. It can be ensuredas a result that channel beat, which could lead to vibrations, does notpractically occur on the roller, which is pretensioned by a spring,e.g., the applicator roller.

The present invention also pertains, furthermore, to a process forengaging and/or disengaging a roller of a printing press with or from afirst mating roller, wherein the roller is engaged with a second matingroller and the roller is guided in the engaged state in the tangentialor circumferential direction of the second mating roller until theroller is engaged or in contact with the first mating roller or isdisengaged therefrom.

The roller now remains continuously in contact with the second matingroller, i.e., a partial area of the roller is in contact with a partialarea of the second mating roller.

The nip, a nip ratio or the pressing pressure or the engaging pressureof the roller can be especially preferably set on one or two matingrollers, e.g., by setting or changing a force acting on the roller in asuitable manner.

The present invention will be described below on the basis of apreferred embodiment. The various features of novelty which characterizethe invention are pointed out with particularity in the claims annexedto and forming a part of this disclosure. For a better understanding ofthe invention, its operating advantages and specific objects attained byits uses, reference is made to the accompanying drawings and descriptivematter in which a preferred embodiment of the invention is illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a schematic diagram of a pneumatic NC applicator rollerbearing;

FIG. 2 is a schematic view of an NC feed unit;

FIG. 3 is an intermediate roller engaged with two stationary matingrollers; and

FIG. 4 is a schematic diagram of an inking and dampening system of anoffset printing press.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings in particular, FIG. 1 shows an embodiment of adevice according to the present invention with an applicator roller 1,which can be adjusted by a basic unit 2 along the surface of thedistributor roller 4 acting as a second mating cylinder. The basic unit2 can be moved according to the present invention preferablypneumatically such that the feed unit 5, in which the applicator roller1 is mounted, is moved such that the applicator roller 1 is guided alongthe circumference of the distributor roller 4 until the applicatorroller 1 is engaged with the plate cylinder 3 provided as the firstmating cylinder. The applicator roller thus remains continuously incontact with the distributor roller 4, as a result of which theapplicator roller 1 is prevented from running dry.

The basic unit 2 can be adjusted transversely in the direction indicatedby the arrows A in order to set a desired nip ratio between theapplicator roller 1 and the plate cylinder 3 or the distributor roller 4by such a transverse adjustment.

The feed unit 5, mounted rotatably in the basic unit 2, has a springelement, which generates a spring pressure on a carriage 8, wherein thethickness of the spring pressure generated by the spring 6 can be set bymeans of the adjusting spindle 7. The applicator roller 1 is mounted bymeans of the carriage 8 in two half shells in the known manner. A nipratio of about 1:1 can be achieved if the feed unit 5 is on the axis ofthe bisecting line of the angle, which bisects the angle 2 a that isformed by the centers of the plate cylinder 3, the applicator roller 1and the distributor roller 4, i.e., if the spring element 6 preferablylies on the bisecting line of the angle such that a pressure that actsapproximately equally on the plate cylinder 3 and on the distributorroller 4. Another nip ratio can be set by deflecting the feed unit 5 orthe spring element 6 pressing the carriage 8 from the bisecting line ofthe angle.

FIG. 2 shows the feed unit 5, which is connected by a hinge 9 to thebasic unit 2 and is mounted rotatably in same.

An adjusting spindle 7, with which the pressure acting on the spring 6can be set, is provided at the feed unit 5. The spring 6 presses thecarriage 8, and an opposite spring 6 a may be optionally provided, whichlikewise presses the carriage 8 in order to compensate, e.g., the weightof the applicator roller 1. The applicator roller 1 is mounted rotatablyin the carriage 8 and can thus be engaged or disengaged, e.g.,pneumatically in an approximately tangential direction in relation tothe distributor roller 4, and the nip at the plate cylinder 3 and/or atthe distributor roller 4 and, in case of a suitable position of thespring 6 or of the feed unit 5, also the nip ratio can be set bypretensioning the spring 6, which is advantageously arrangedapproximately along the above-described bisecting line of the anglebetween the plate cylinder 3 and the distributor roller 4.

For example, the applicator roller 1 and the distributor roller 4 are infunctional connection and there is no functional connection between theapplicator roller 1 and the plate cylinder 3 during the run-up of theprinting press. At the beginning of the printing operation, theapplicator roller 1 is engaged with the plate cylinder 3 whilemaintaining the functional connection with the distributor roller 4 andis again disengaged from the plate cylinder 3, e.g., to perform awashing operation, in order to be then in functional connection with thedistributor roller 4 only.

FIG. 4 shows a schematic view of an inking and dampening system of anoffset printing press and shows as an example rollers that are engagedand/or disengaged with the device according to the present invention orthe process according to the present invention. In particular, therollers mentioned by name and/or also rollers that are directly orindirectly adjacent to same can also be engaged or disengaged with thedevice according to the present invention with the mating cylindersshown.

Even though it was described in the exemplary embodiment that theapplicator roller 1 is guided along the distributor roller 4 in order toengage this applicator roller with the plate cylinder 3, the reverseprocedure is possible, in principle, as well.

While specific embodiments of the invention have been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

1. A device for engaging and/or disengaging a roller with or from afirst mating roller, with a second mating roller, with which the rolleris engaged, the device comprising: a basic unit, with which the rollercan be moved to or away from the first mating roller in thecircumferential direction of the second mating roller.
 2. A device inaccordance with claim 1, wherein the basic unit has a pneumaticadjusting element.
 3. A device in accordance with claim 1, wherein thebasic unit can be adjusted in parallel to a tangential direction of thesecond mating roller.
 4. A device in accordance with claim 1, furthercomprising: a feed unit, with which an engaging pressure can begenerated on at least one of the mating rollers.
 5. A device inaccordance with claim 4, further comprising a spring element forgenerating the engaging pressure of the roller.
 6. A device inaccordance with claim 1, with a setting element for setting the engagingpressure.
 7. A device in accordance with claim 1, wherein the roller ismounted in a carriage.
 8. A process for engaging and/or disengaging aroller of a printing press with or from a first mating roller, whereinthe roller is engaged with a second mating roller and the roller isguided in the circumferential direction of the second mating roller inthe state in which it is engaged with the second mating roller.
 9. Aprocess in accordance with claim 8, wherein the roller is continuouslyin contact with the second mating roller.
 10. A process in accordancewith claim 8, wherein a nip, a nip ratio or the engaging pressure is setin the state in which the two mating rollers are engaged.
 11. A printingpress system, comprising: a first mating roller; a second mating roller;an engagement roller for engaging and/or disengaging with or from thefirst mating roller and for engagement with the second mating roller; abasic unit, with which the roller can be moved to or away from the firstmating roller in the circumferential direction of the second matingroller.
 12. A system in accordance with claim 11, wherein the basic unithas a pneumatic adjusting element.
 13. A system in accordance with claim12, wherein the basic unit can be adjusted in parallel to a tangentialdirection of the second mating roller.
 14. A system in accordance withclaim 11, further comprising a feed unit, with which an engagingpressure can be generated on at least one of the mating rollers.
 15. Asystem in accordance with claim 11, further comprising a spring elementfor generating the engaging pressure of the roller.
 16. A system inaccordance with claim 11, with a setting element for setting an engagingpressure.
 17. A system in accordance with claim 11, wherein theengagement roller is mounted in a carriage.